Extraction Of Materials Research Articles

Phytic Acid Functionalized Hierarchical Porous Metal-Organic Framework Microspheres for Efficient Extraction of Uranium from Seawater.

Uranium is a critical resource in the development of nuclear energy, and its extraction from natural seawater has been identified as a potential solution to address uranium resource shortages. In this study, hierarchical meso-/micro- porous metal-organic framework functionalized with phytic acid (PA) microspheres (denoted H-UiO-66-PA) are rationally synthesized for efficient uranium extraction. This unique design allowed for a large adsorption capacity and fast adsorption kinetics, making it a promising material for uranium extraction. Due to the hierarchically porous structure, H-UiO-66-NH2 materials not only provide more sites for grafting PA, and thus enhance the adsorption capacity, but also facilitate the rapid diffusion of uranyl ions which can quickly and effectively access the interior of the H-UiO-66-PA adsorbent. Therefore, the obtained H-UiO-66-PA can achieve an impressive absorption efficiency of 6.76mgg-1 in actual seawater within 15 days. Meanwhile, the H-UiO-66-PA possesses a good adsorption capacity for uranyl ions in the five adsorption/desorption cycles. This work proposes a feasible strategy for constructing functional hierarchical porous MOFs for uranium removal.

A Spray-Dried Self-Stabilizing Nanocrystal Emulsion of Traditional Chinese Medicine: Preparation, Characterization and ex vivo Intestinal Absorption

AbstractSalvia miltiorrhizae (Danshen, the rhizome of Salvia miltiorrhiza Bge.) and Chuanxiong rhizome (Chuanxiong, the rhizome of Ligusticum chuanxiong Hort.) are two traditional Chinese medicines that have been widely used for the treatment of cardiovascular and cerebrovascular diseases. However, formulation development is difficult due to the complexity of the active ingredients, particularly the water-insoluble tanshinones and volatile oil of Chuanxiong rhizome, which cannot be absorbed via oral administration in conventional dosage forms. This study aimed to develop a self-stabilized nanocrystal emulsion co-loading the water-soluble, insoluble, and volatile active ingredients of Salvia miltiorrhizae and Chuanxiong rhizome to improve the bioavailability of the drugs. In this work, a high-pressure homogenization method was used to prepare a self-stabilizing nanocrystal emulsion. The emulsion was then spray-dried using hydroxypropyl-β-cyclodextrin. The dispersibility and storage stability of the spray-dried emulsion, the particle size and morphology of the emulsion droplets, and the drug content and phase distribution of the reconstituted emulsion were evaluated. An everted intestinal sac model was established, and high-performance liquid chromatography was used to determine the concentration of six active components (ferulic acid, salvianolic acid B, senkyunolide A, ligustilide, cryptotanshinone, and tanshinone IIA) and to assess the cumulative uptake amount of the drug and the apparent permeability coefficient. A mixture of the crude materials of tanshinones extract, total salvianolic acid, ferulic acid, and volatile oil of Ligusticum Chuanxiong was used as a control. The results showed that the spray-dried emulsion can be easily reconstituted into a uniform submicron emulsion with no significant changes in particle size, morphology, and microstructure of the emulsion droplets compared with the original emulsion before drying. The self-stabilizing nanocrystal emulsion significantly improved the intestinal absorption of water-insoluble components (tanshinone IIA, cryptotanshinone, and ferulic acid), and volatile oil components (senkyunolide A and ligustilide). Overall, the spray-dried self-stabilizing nanocrystal emulsion represents a potential oral formulation for Salvia miltiorrhiza and Chuanxiong rhizoma.

Green and Mild Fabrication of Magnetic Poly(trithiocyanuric acid) Polymers for Rapid and Selective Separation of Mercury(II) Ions in Aqueous Samples.

The removal and detection of highly toxic mercury(II) ions (Hg2+) in water used daily is essential for human health and monitoring environmental pollution. Efficient porous organic polymers (POPs) can provide a strong adsorption capacity toward heavy metal ions, although the complex synthetic process and inconvenient phase separation steps limit their application. Hence, a combination of POPs and magnetic nanomaterials was proposed and a new magnetic porous organic polymer adsorbent was fabricated by a green and mild redox reaction in the aqueous phase with trithiocyanuric acid (TA) and its sodium salts acting as reductive monomers and iodine acting as an oxidant. In the preparation steps, no additional harmful organic solvent is required and the byproducts of sodium iodine are generally considered to be non-toxic. The resulting magnetic poly(trithiocyanuric acid) polymers (MPTAPs) are highly porous, have large surface areas, are rich in sulfhydryl groups and show easy magnetic separation ability. The experimental results show that MPTAPs exhibit good adsorption affinity toward Hg2+ with high selectivity, rapid adsorption kinetics (10 min), a large adsorption capacity (211 mg g-1) and wide adsorption applicability under various pH environments (pH 2~8). Additionally, MPTAPs can be reused for up to 10 cycles, and the magnetic separation step of MPTAPs is fast and convenient, reducing energy consumption compared to centrifugation and filtration steps required for non-magnetic adsorbents. These results demonstrate the promising capability of MPTAPs as superior adsorbents for effective adsorption and separation of Hg2+. Based on this, the prepared MPTAPs were adopted as magnetic solid-phase extraction (MSPE) materials for isolation of trace Hg2+ from aqueous samples. Under optimized conditions, the extraction and quantification of trace Hg2+ in water samples were accomplished using inductively coupled plasma mass spectrometry (ICP-MS) detection after MSPE procedures. The proposed MPTAPs-based MSPE-ICP-MS method is efficient, rapid, sensitive and selective for the determination of trace Hg2+, and was successfully employed for the accurate analysis of trace Hg2+ in tap water, wastewater, lake water and river water samples.

PHYTOCHEMICAL CONTENTS, GC-MS PROFILE AND ALPHA-AMYLASE INHIBITORY POTENTIAL OF Rauwolfia vomitoria n-HEXANE ROOT EXTRACT

Rauwolfia vomitoria is a tropical medicinal plant that has been used traditionally in the management of several diseases. In this study, the phytocontents and the preliminary alpha-amylase inhibitory activity of the n-hexane extracts of R. vomitoria was investigated. The dried plant material, R. vomitoria root was extracted by macerating in n-hexane for 72 h. The phytochemical screening and quantity of the alkaloids, flavonoid, and saponins in the extract and plant materials was determined using standard methods. The Preliminary alpha amylase inhibitory activity of the extract was carried out using starch iodide reagent assay. The phytochemical contents of the root extract were determined out using Gas Chromatography and Mass spectrophotometry (GC-MS). The extraction of R. vomitoria yielded 2.30% n-Hexane extract. The phytochemical screening of the extract shows the presence of alkaloid, flavonoid, saponins, reducing sugar, de-oxy sugars and steroids while quantitative phytochemical analysis showed the root contain alkaloids: 11.2±0.06, flavonoids: 16.6 ±0.12 and saponins: 14.8 ±0.18. The extract gave a positive alpha-amylase inhibitory activity. The GC-MS indicated the presence of twelve compounds, which are basically long chain fatty acids and esters and the most abundant compound is n-Hexadecanoic acid. Most of the compounds detected have antioxidant, anti-inflammatory, antidiabetic and enzyme inhibitory activities which may explain the various traditional uses of this plant and the observed alpha-amylase inhibitory activity

Analytical insight into caffeine extraction from typica coffee leaves based on crystallinity enhancement, optical phonon vibration upshift, and morphological evolution.

Caffeine extracted from callus cultures by in vitro technique induced from typica coffee (Coffea arabica L. var. typica) leaves was successfully carried out by a simple Soxhlet method. Analysis of X-ray diffraction patterns showed an increase in crystallinity fraction from leaves (13.56%) to callus (14.46%) and then to caffeine (39.18%). Crystallite size also varied, with average sizes of 18±6, 69±51, and 32.5±17 nm for leaves, callus, and caffeine, respectively. Fourier transmission infrared absorption data confirmed the presence of hydroxyl (OH) groups bound to carbon (C─COH), indicating caffeine content. The high stability of the C─COH is indicated by the broad optical phonon vibrations of the leaves: 247cm-1 to caffeine: 963cm-1. Quantitative analysis of dielectric function and electron loss function intensity peaks of each sample showed that leaves efficiently capture and store light energy while caffeine has less potency. Scanning electron microscopy analysis showed irregular shapes of leaves, oval round shapes for callus, and rectangular crystals for caffeine due to crystal orientation during transformation and had a strong correlation with crystallinity fraction. Finally, the structure-based identification, chemistry, optical-dielectric function, and micro-surface properties have been fully studied, thus unmasking the phenomenon of slow transformation from leaves to caffeine form. PRACTICAL APPLICATION: The result of this study can be applied to uncover new methodologies related to the classification, and biotechnological utilization of callus culture based on structural properties, optical-dielectric function, and micro-surface analysis. Methodologically, the resulting callus culture provides a sustainable and controllable supply of plant material for caffeine extraction, thereby reducing traditional methods involving field-grown plants and avoiding the use of pesticides.

Analysis of Magnetization Dynamics in NiFe Thin Films with Growth-Induced Magnetic Anisotropies

We have used angled magnetron sputter deposition with and without sample rotation to control the magnetic anisotropy in 20 nm NiFe films. Ferromagnetic resonance spectroscopy, with data analysis using a Bayesian approach, is used to extract material parameters relating to the magnetic anisotropy. When the sample is rotated during growth, only shape anisotropy is present, but when the sample is held fixed, a strong uniaxial anisotropy emerges with in-plane easy axis along the azimuthal direction of the incident atom flux. When the film is deposited in two steps, with an in-plane rotation of 90 degrees between steps, the two orthogonal induced in-plane easy-axes effectively cancel. The analysis approach enables precise and accurate determination of material parameters from ferromagnetic resonance measurements; this demonstrates the ability to precisely control both the direction and strength of uniaxial magnetic anisotropy, which is important in magnetic thin-film device applications.

A Hollow Hemispherical Mixed Matrix Lithium Adsorbent with High Interfacial Interaction for Lithium Recovery from Brine

Mixed matrix lithium adsorbents have attracted much interest for lithium recovery from brine. However, the absence of an interfacial interaction between the inorganic lithium-ion sieves (LISs) and the organic polymer matrix resulted in the poor structural stability and attenuated lithium adsorption efficiency. Here, a novel hollow hemispherical mixed matrix lithium adsorbent (H-LIS) with high interfacial compatibility was constructed based on mussel-bioinspired surface chemistry using a solvent evaporation induced phase transition method. The effects of types of functional modifiers, LIS loading amount, adsorption temperature and pH on their structural stability and lithium adsorption performance were systematically investigated. The optimized H-LIS adsorbent with the LIS loading amount of 50 wt.% possessed the structural merit that the LIS functionally modified by dopamine exposed on both the inner and outer surfaces of the hollow hemispheres. At the best adsorption pH of 12.0, it showed a comparable lithium adsorption capacity of 25.68 mg·g−1 to the powdery LIS within 4 h, favorable adsorption selectivity of Mg/Li and good reusability that could maintain over 90% of lithium adsorption capacity after the LiCl adsorption—0.25 M HCl pickling-DI water cleaning cycling processes for three times. The interfacial interaction mechanism of H-LIS for lithium adsorption was innovatively explored via advanced microcalorimetry technology. It suggested the nature of the Li+ adsorption process was exothermic and dopamine modification could reduce the activation energy for lithium adsorption from 15.68 kJ·mol−1 to 13.83 kJ·mol−1 and trigger a faster response to Li+ by strengthening the Li+-H+ exchange rate, which established the thermodynamic relationship between the structure and Li+ adsorption performance of H-LIS. This work will provide a technical support for the structural regulation of functional materials for lithium extraction from brine.

The carbon crater: Comparing anthropogenic greenhouse gas emissions to historical planetary events

Equilibrium climate sensitivity modeling relies heavily on paleoclimate records that were affected by meteorite impacts and volcanic explosions. This paper conducts a thought experiment by re-assembling known data and theories to shed new light on anthropogenic carbon waste. Anthropogenic activity, meteorite impacts and volcanic explosions all extract material from the Earth’s crust and deposit it in the atmosphere. This thought experiment tests if the mass of anthropogenic greenhouse gas emissions from 1851 to 2021 is comparable to the mass of atmospheric emissions from historical planetary events. Approximately 3.60 trillion tons of anthropogenic carbon dioxide equivalents are converted into volume and then transformed into the shape of a meteorite impact structure named the “Carbon Crater.” The 35 km crater (bounded by 34%–68% confidence intervals of 25–45 km) would rank 23rd on the list of known impact structures. The 2.6 km projectile required to create the Crater would be a 10 on the 1–10 Torino hazard scale described as “. . .capable of causing global climatic catastrophe. . .” The estimated re-occurrence interval for a projectile of this size is 5.3 million years. An interval of this time in Earth’s recent history predates homo sapiens. The Crater’s volume is exponentially larger than the 1883 eruption of Krakatoa and ranks as an 8 (“mega-colossal”) on the 0–8 Volcanic Explosivity Index. The thought experiment indicates that the Carbon Crater’s scale is comparable with large historical biospheric events. These results likely confer few direct implications for the study of the paleoclimate in climate modeling but might change conceptual understandings of atmospheric human waste. Additional empirical research is required to understand the potential impact of the Carbon Crater on conceptual change.

Physical, functional and bioactive properties of microencapsulated powders from banana pseudostem and inflorescence extracts

Application of agricultural by-products in the functional food and beverage industry is currently gaining prominence. Banana (Musa spp) is a popular tropical fruit with global production of 124.97 million tonnes. The banana production industry contributes to large amount of solid waste/ banana by-products, such as, pseudostem and inflorescence. Palayankodan (Musa × paradisiaca Mysore AAB group), Nendran (Musa × paradisiaca AAB group) and Njalipoovan (Musa × paradisiaca AB group) are three popular and common cultivars in Kerala, a state in South India. The present study was aimed to extract the potential bioactive compounds from the pseudostem and inflorescence of the above-mentioned cultivars and to standardise the process of microencapsulation using spray drying. Ultrasonication assisted extraction using ethanol as solvent was carried out. The extract and wall material parameters were standardised for microencapsulation. The encapsulated powders were analysed for encapsulation yield, retention efficiency, physical properties, phytochemical composition, antioxidant potential and anti-diabetic activity. The encapsulation yields and retention efficiencies of the encapsulated powders were found to be approximately 75 and 70.51%, respectively. Results revealed that the powders exhibited lower bulk density, good solubility and reconstitutability. Scanning electron microscopy was also conducted to reveal the particle morphology. All the powders exhibited smooth, spherical shape, with no pores. The phenolic and flavonoid contents of the encapsulated pseudostem and inflorescence extract powders ranged from 2.75 to 3.13 mg GAE/ g of powder and 34.83 to 46.67 mg QE/g of powder, respectively. The present study also reported the in vitro bioactive properties, in terms of antioxidant and anti-diabetic activities of the encapsulated powders. The HPLC analysis of the microencapsulated powders revealed the presence of gallic acid, protocatechuic acid, trans cinnamic acid, trans ferulic acid, epicatechin and syringic acid. It is clear from the study that the encapsulated powders from banana by-products have a great potential to be utilised by the functional food industry.Graphical

New Perspectives on the Old Uses of Traditional Medicinal and Edible Herbs: Extract and Spent Material of Persicaria hydropiper (L.) Delarbre

Background/Objectives:Persicaria hydropiper (L.) Delarbre, commonly known as water pepper, possesses multifunctional potential. Our research focuses on its complex phenolic composition, bioactivity, safety evaluation and utilization in a sustainable manner. Moreover, a survey was conducted among the Serbian population to gain insight into the attitude towards traditional wild-growing herbs (i.e., P. hydropiper), the level of familiarity with their zero-waste culture, and to assess eating behaviors. Methods: A survey was conducted with 168 participants to assess attitudes towards traditional herbs, zero-waste culture, and eating behaviors, while cytotoxicity, in vivo toxicity, chemical analysis of secondary metabolites, and probiotic viability assays were performed to evaluate the effects of the PH extract. Results: Notably, P. hydropiper extract (PH) exhibits a diverse phenolic profile, including quinic acid (3.68 ± 0.37 mg/g DW), gallic acid (1.16 ± 0.10 mg/g DW), quercetin (2.34 ± 0.70 mg/g DW) and kaempferol-3-O-glucoside (4.18 ± 0.17 mg/g DW). These bioactive compounds have been linked to anticancer effects. The tested extract demonstrated a cytotoxic effect on the human neuroblastoma cell line, opening questions for the further exploration of its mechanisms for potential therapeutic applications. Based on the toxicity assessment in the Artemia salina model, the PH could be characterized with good safety, especially for the lower concentrations (LC50 = 0.83 mg/mL, 24 h). The utilization of the spent PH material supports the viability of psychobiotic strains (up to 9.26 ± 0.54 log CFU/mL). Based on the conducted survey, 63.7% (n = 107) of respondents mainly prefer traditional instead of imported herbs. The respondents were skeptical about zero-waste edibles; 51.2% (n = 86) would not try them, and a bit more than half were not familiar with zero-waste culture (57.7%; n = 97). Only 8.3% (n = 14) followed a flexitarian diet as a dietary pattern. Conclusions: The use of underutilized traditional plants and their spent material could potentially contribute to the acceptance of a zero-waste culture in Serbia. Reinventing the use of neglected traditional plants and addressing ways for spent material valorization could contribute to the acceptance of a zero-waste strategy and encourage healthier eating behavior.

Microwave-assisted supramolecular double crosslinked chitosan-based molecularly imprinted polymer for synergistic recognition and selective recovery of Cd(II) and As(V) from water: Performance and mechanistic insights

A novel model of the sustainable double crosslinked molecularly imprinted polymer (D-Crosslinked MIP) represented as a supramolecular imprinted polymer was synthesized via the bulk polymerization method. The primary crosslinking was fabricated using biomacromolecule chitosan as a functional monomer and glutaraldehyde as a crosslinker. The primary crosslinked was subjected to dynamic interactions in a secondary crosslinking by binding Al2O3-NPs and TiO2-NPs, forming the supramolecular D-Crosslinked-MIP. The dually crosslinked formed from combining three distinct crosslinkers in one system for the interaction with As(V) and Cd(II). A microwave was employed to evaluate the performance of the designed material in selectivity and extraction of metal ions from water. The FT-IR, XRD, TG/DTA, SEM-EDX, TEM, and XPS were used to verify the characteristics of (D-nano-Al2O3@Crosslinked Chitosan@D-nano-TiO2). The type of solvents, selectivity, interferences, microwave-contact time, pH, temperatures, concentrations, and regeneration were investigated. By using the D-Crosslinked-MIP, at 15 s, Cd(II) revealed a recovery capacity of 99.03 %, Qmax 862.07 mg/g, while As(V) demonstrated a recovery capacity of 99.06 %, Qmax 850.75 mg/g. The D-Crosslinked-MIP exhibited BETs of 69.01 m2/g with a pore volume of 0.2340 cm3/g owing to polymeric crosslinking by metal oxide NPs. The kinetics, isotherm models, and mechanisms of dually crosslinking and extraction of toxic metals were discussed.

Mechanism of selective uranium adsorption using polyvinyl alcohol /Cyphos IL-101 / reduced graphene oxide composites

A novel composite material for uranium extraction from seawater, APGO, was prepared by crosslinking reduced graphene oxide (rGO) loaded with trihexyl(tetradecyl)phosphonium chloride (Cyphos IL-101) with polyvinyl alcohol. The experimental results indicate that the surface of APGO contains functional groups, such as carboxyl, hydroxyl, and phosphate, that have adsorption properties for uranium. APGO exhibits excellent hydrophilicity and stability while preserving the intact two-dimensional network structure of rGO. The specific surface area of APGO was 9.23 m2/g with an average pore size of 27.50 nm. Furthermore, the optimal pH range for APGO to adsorb uranium is 6–8, making it more suitable for extracting uranium from seawater. Notably, the selective adsorption capacity of APGO for uranium is significantly enhanced compared to that of AGO, with a Kd value approximately 4.6 times higher than that of AGO. The theoretical adsorption capacity is 467mg/g at 318 K (pH = 6). The process of uranium adsorption by APGO is a spontaneous endothermic reaction. The adsorption performance of APGO is noteworthy because it exhibits only a 2 % decrease after five adsorption–desorption cycles. Furthermore, APGO demonstrates commendable recyclability. Overall, APGO demonstrates a remarkable affinity for uranium and promising potential for efficiently extracting uranium from seawater.

INVESTIGATION OF THE EFFICIENCY OF RHENIUM ION SORPTION USING ION-EXCHANGE RESINS POLYACRYLIC ACID: POLY-4-VINYLPYRIDINE IN VARIOUS RATIOS

This study is devoted to the study of the efficiency of sorption of rhenium ions using ion-exchange resins containing polyacrylic acid (PAK) and poly-4-vinylpyridine (P4VP) in various composition ratios. Goals and objectives. To investigate synthesized resins with different ratios of PAK:P4VP and to study their sorption capacity, kinetics and selectivity with respect to rhenium ions. Methods. Thanks to a comprehensive experimental analysis, including periodic sorption experiments and characterization methods such as spectrophotometry and atomic emission spectroscopy, the effect of resin composition on sorption efficiency was clarified during the study. Results and discussion. Optimal ratios have been determined to ensure maximum efficiency of rhenium ion removal. In addition, the study examines the main mechanisms governing sorption properties, with an emphasis on the relationship between resin composition, surface chemical composition and ion interaction. Conclusion. The results obtained contribute not only to the development of special ion-exchange materials for the effective extraction and purification of rhenium, but also contribute to a deeper understanding of ion sorption processes. This research has important implications for rhenium-dependent industries, offering strategies for solving problems related to its extraction, purification and use.

Explosive Ordnance Detection in Areas Designated for Mining

Nowadays, mining is becoming increasingly valued, as mines of various types provide a large part of the raw materials needed for construction. In order to ensure a continuous supply of extraction and raw materials, new areas need to be identified and opened up. However, some of these new areas may contain security risks such as explosive remnants of war. If we look back to the events of the World War II, there was perhaps no area in Europe that was not affected by the preparation or execution of some act of war. The warring parties deployed a full arsenal of weapons, some of which still pose a threat today. The various types of bombs, mines, projectiles and grenades were only partially operational. Explosive devices that were simply left behind or unexploded were buried beneath the surface, and continue to pose a growing threat to this day (almost eight decades later). The dismantling and disposal of the left-behind and often very poorly recovered explosive devices has been ongoing ever since. The problems of finding explosive devices and munitions tend to occur in areas where there has been no previous investment, construction or earthworks.

REGENERATION OF SECONDARY ASPHALT PAVEMENTS WITH REJUVENATING AGENTS

Recycling reclaimed asphalt pavement fulfills an important function in achieving a sustainable and environmentally friendly road construction industry. Using reclaimed asphalt pavement (RAP) it is possible to produce new asphalt with a small amount of virgin raw materials. This will reduce the amount of energy required to extract and process virgin asphalt pavement materials, along with the amount of waste generated during road reconstruction. Despite these advantages, road agencies have been reluctant to use high proportions of RAP materials in new asphalt production because the presence of large amounts of oxidized bitumen from RAP in new mixtures makes them less workable and less compactable than mixtures with virgin bitumen alone. One should also be aware of the high stiffness of RAP mixtures, which will make them difficult to use. Various methods can be used to overcome this problem, one of the most effective is the addition of rejuvenating agents. This article describes research into the production of asphalt mixtures from recycled asphalt pavement (RAP) material. This work aims to study the effectiveness of various rejuvenators for restoring the basic performance characteristics of asphalt pavements. The most effective rejuvenators and their classification are reviewed. The hypothesized mechanism of rejuvenation of asphalt pavements by the introduction of rejuvenators is presented. The methods of introducing various rejuvenators into RAP are described.

Development of Student Handbook on the Extraction of Secondary Metabolites Based on Premna serratifolia Research

This study aims to develop a digital module on the extraction of secondary metabolites based on P. serratifolia research as a self-study resource for students. This study utilized the Thiagarajan 4D development model, which encompasses the stages of definition, design, and development without dissemination. Participants in the study comprised students from Universitas Muhammadiyah Pontianak, Akademi Farmasi Yarsi Pontianak, and Universitas Tanjungpura who had previously studied extraction materials. Subject matter, media, and language experts provided validity scores of 94.69%, 88%, and 84.37%, respectively, resulting in an average validity score of 89.02%, categorizing the student handbook as highly valid. Small and large group trials yielded practicality percentages of 93.81% and 93.69%, respectively, with an average score of 93.75%, indicating the student handbook high practicality. Consequently, the student handbook on secondary metabolite extraction based on P. serratifolia research is deemed highly valid and practical as a self-study resource on the topic.

Characterization of mango seed kernel starch: Extraction and Analysis

During mango (Mangifera indica) processing, significant by-products like peel and kernel are generated. Mango seed kernels are cost-effective and readily available materials for starch extraction. This study explores low-cost methods to extract mango kernel starch (MKS) from Surjapuri (X) and Amrapali (Y) varieties using distilled water and alkaline solution. Proximate analysis revealed starch yield variations from 44.49 % to 62.11 %, with moisture content between 4.32 % and 5.89 %, protein content from 0.067 % to 0.069 %, fat content from 0.22 % to 0.24 %, and ash content from 0.12 % to 0.14 %. X-variety starch extracted using distilled water had a higher yield (62.11 %), foaming capacity (5.94 %), and emulsion capacity (6.36 %), while alkaline extraction showed higher water absorption (0.16 %) and oil absorption (0.15 %). Y-variety starch showed higher amylose content (23.50 %) with distilled water extraction and higher pH (7.94) with alkaline extraction. X-variety starch had higher swelling power (11.35 g g-1) with distilled water extraction and higher solubility (0.27 %) with alkaline extraction at 90 °C. Principal component analysis (PCA), Heat map, and Pearson correlation analyses highlighted significant relationships between proximate and physicochemical properties. These results suggest that distilled water extraction is an effective, low-cost method for isolating high-quality MKS, with potential applications in various industries.

Sustainable Removal of Cr(VI) from Wastewater Using Green Composites of Zero-Valent Iron and Natural Clays

Composites for efficient removal of hexavalent chromium Cr(VI) from industrial wastewater were obtained by deposition of nano-zero-valent iron (nZVI), synthesized by environmentally friendly synthesis using oak leaf extract, on inexpensive, natural, readily available and cheap natural raw materials, sepiolite (SEP) or kaolinite/illite (KUb) clay, as support. nZVI particles were deposited from the FeCl3 solution of different concentrations, with the same volume ratio extract/FeCl3 solution (3:1), and with different masses of SEP or KUb. Physico–chemical characterization (SEM/EDS, FTIR, BET, determination of point of zero charge) of the composites and nZVI was performed. The results of SEM and BET analyses suggested more homogeneous deposition of nZVI onto SEP than onto KUb, which ensures greater availability of the nZVI surface for Cr(VI) anions. Therefore, the higher Cr(VI) removal at all investigated initial pH values (pHi) of the solution (3, 4 and 5) was achieved with the SEP composites. The adsorption results indicated that the elimination of Cr(VI) was achieved via the combined effect of reduction and adsorption. The removal of total chromium at pHi = 3 was approximately the same as that of Cr(VI) removal for the KUb composites, but lower for the SEP composites, indicating lower removal of Cr(III) compared to the reduced Cr(VI). The SEP/nZVI composite with the highest removal efficiency was applied for Cr(VI) removal from real wastewater at pHi = 3 and pHi = 5. The results demonstrated the high Cr(VI) removal capacity, validated the assumption that a good dispersion of nZVI particles is beneficial for Cr(VI) removal and showed that the produced green composites can be efficient materials for the removal of Cr(VI) from wastewater.

One-step hot-press synthesis of amino functionalized Zr-based metal organic framework for determination and speciation of trace inorganic arsenic species in water samples with EDXRF spectrometry

Herein, amino functionalized Zr-based metal organic framework (UiO-66-NH2) on carbon cloth substrate was synthesized by using one-step hot-pressing method and the product (UiO-NH2@CC) was evaluated as a new solid phase extraction (SPE) material for determination and speciation of inorganic arsenic species (As(V) and As(III)) in water samples through energy dispersive X-ray fluorescence (EDXRF) spectrometry. SPE efficiency of UiO-NH2@CC was examined in batch and continuous adsorption (pre-concentration) processes and combination of either batch or continuous pre-concentration process with EDXRF spectrometry proposed analytical method, offering remarkable benefits (i.e., user-friendly, no elution procedure, environmentally friendly and cost-effective, etc.). Batch adsorption studies indicated that As(V) could be selectively adsorbed by UiO-NH2@CC at pH 2 and better represented by Freundlich isotherm model in 60 min of equilibrium time. Continuous adsorption studies at pH 2 demonstrated a drop in As(V) adsorption efficiency of UiO-NH2@CC for sample loading volume above 30 mL with increasing flow rate from 0.3 to 1.0 mL/min and initial As(V) concentration from 20 to 100 µg/L. By considering fortification experiments on real water samples at two levels (5 and 50 µg/L) of As(V) species, both batch and continuous pre-concentration steps coupled with EDXRF spectrometry, with LOD values of 0.790 and 0.220 µg/L, respectively, indicated good recoveries in the range of 87(±11)–104(±7) with no statistically significant differences. Finally, the continuous pre-concentration step followed by EDXRF measurement, as a representative analytical method, was of successful applicability to the speciation of As(III) and As(V) in real water samples with notable advantages (i.e., effortless, economical, practical and reproducible, etc.).

Supercritical fluid extraction of coumarins and flavonoids from citrus peel

The production manufacture of juices generates a large amount of waste consisting mainly of fruit peels. The peels are source of molecules such as coumarins and flavonoids. In this study, the peels of Citrus limonia, Citrus deliciosa, Citrus latifolia and Citrus sinensis were the raw material for supercritical fluid extraction. The Box-Behnken design was used to optimize the global yield in function of process variables. The chemical analysis of the extract was carried out by LC-MS and GC-MS. CFD was applied to the mass and momentum conservation equations in the study of supercritical extraction using citrus peels, which allowed the determination of unknown parameters of the bidimensional mathematical model. The flavonoids, nobiletin, sinensetin and tangeretin, as well as the coumarin, citropten, were identified in all species investigated. The maximum global yield obtained were 3.93 % for Citrus limonia, 4.18 % for Citrus deliciosa, 3.48 % for Citrus latifolia and 5.32 % for Citrus sinensis.